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Discussion Starter · #1 · (Edited)
I guess it could happen to any Ti weld from any company???
In one week:
1- heard a squeak in the head set, thought it was my head set going, turned out to be a crack in the weld -headtube
2- my seat had a squeak, then snapped off at the weld. Lucky I was just riding in my drive way checking my brakes

I ride cross country rigid and weight about 165lbs -

Just wondering if this is normal for all welded TI?
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Shamisen Appreciator
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I guess it could happen to any Ti weld from any company???
In one week:
1- heard a squeak in the head set, thought it was my head set going, turned out to be a crack in the weld -headtube
2- my seat had a squeak, then snapped off at the weld. Lucky I was just riding in my drive way checking my brakes

I ride cross country rigid and weight about 165lbs -

Just wondering if this is normal for all welded TI?
View attachment 1255047 View attachment 1255041 View attachment 1255039 View attachment 1255037
I can't see what's going on with that head tube, it would help to see the inside. You can clearly see evidence of bad backpurge on the seat post. It's a scaly mess in there and my guess is that whoever welded it didn't have it positioned correctly or didn't wait long enough. If it was no purge at all, you'd see the scale further into the tube. You can also see evidence of a cold weld on the last photo...on the left hand side there's a clear line that separates the weld bead from the actual tube...in fact you can pretty much see the whole mitered end of the tube...which means that it didn't get a root pass and the filler pass didn't get hot enough for proper penetration. My guess is the welder didn't want to key open the clamp tube by giving it proper heat.
 

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When I took this one to a local builder to be repaired, he mentioned that he has stopped building frames with short head tubes that require "stacking" the top tube and down tube because he has seen several crack at this junction. Apparently this causes a different set of stresses than if the tubes were welded around the entire circumference. He now prefers to build with a taller head tube so that he can get full circumference welds around both the down tube and the top tube at their intersection with the head tube.

 

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When I took this one to a local builder to be repaired...
That is not safely repairable, unless by "repair" you mean replacing the entire front end of the bike... did someone actually weld those cracks and give you back the frame? If so, stop riding it right now.

-Walt
 

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That is not safely repairable, unless by "repair" you mean replacing the entire front end of the bike... did someone actually weld those cracks and give you back the frame? If so, stop riding it right now.

-Walt
He drilled holes at the end of the cracks and then welded. I've got about 1000 trail miles on the bike with no issues since then, but keeping a close eye on it.

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Shamisen Appreciator
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He drilled holes at the end of the cracks and then welded. I've got about 1000 trail miles on the bike with no issues since then, but keeping a close eye on it.

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That's all well and good and I'm glad it hasn't come apart on you but the underlying problem hasn't been addressed. The surface has been patched and that's it. We don't know why it cracked but it's a safe bet that either there's some internal contamination or there was a gap where the TT and DT joined the HT and it wasn't fully welded. Laying down more filler doesn't fix it and it's a matter of time before it cracks again. I wrote a multipage post on MTBR a number of years ago and am not inclined to do it again. If you're interested, maybe search for it and get a little education.
 

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That's all well and good and I'm glad it hasn't come apart on you but the underlying problem hasn't been addressed. The surface has been patched and that's it. We don't know why it cracked but it's a safe bet that either there's some internal contamination or there was a gap where the TT and DT joined the HT and it wasn't fully welded. Laying down more filler doesn't fix it and it's a matter of time before it cracks again. I wrote a multipage post on MTBR a number of years ago and am not inclined to do it again. If you're interested, maybe search for it and get a little education.
Thank you. I'll look for the post.
 

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He drilled holes at the end of the cracks and then welded. I've got about 1000 trail miles on the bike with no issues since then, but keeping a close eye on it.
I would have refused to do that repair, personally. Good luck, and yes, keep a very close eye on it.

-Walt
 
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